Add PyCode_GetCode() function

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Wait until python/cpython#92168 is merged.

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Nit: PyCodeObject *code not PyObject *code :)

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Fixed in commit bed155e.

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Not sure if it matters, but this code will fail on one version: 3.11a7. In that version, co_code was removed, but there is no PyCode_GetCode.

I don't know what you should do here. Maybe exclude that version?

[erlend-aasland]

Perhaps #error with an explanatory message.

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I don't know what you should do here. Maybe exclude that version?

Alpha versions of Python 3.11 are not supported:

pythoncapi-compat/tests/test_pythoncapi_compat.py

Lines 152 to 157 in c9764f5

	# Implementing PyFrame_GetLocals() and PyCode_GetCode() require the
	# internal C API in Python 3.11 alpha versions
	if 0x30b0000 <= sys.hexversion < 0x30b00b1:
	version = sys.version.split()[0]
	print("SKIP TESTS: Python %s is not supported" % version)
	return

It's a deliberate choice to not pollute pythoncapi_compat.h with ugly code to tons of compatibility layers, whereas there are few users of Python alpha versions.

Perhaps #error with an explanatory message.

What I suggested to users who want to upgrade pythoncapi_compat.h before Python 3.11 beta1 is to copy the file and then remove the functions which cause compilation errors. It's being discussed at: #32

[erlend-aasland]

Ok, makes sense.

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I'm not against adding an #error if you consider that it will help users impacted by this issue.

Python 3.11 beta1 is scheduled in a few days.

Python 3.11 breaks tons of C API: https://docs.python.org/dev/whatsnew/3.11.html#c-api-changes

In the past, I tried first to add getter functions in one Python version, and only change the structure in the following Python version. Well, the optimization work broke many structures (PyThreadState, PyFrameObject, PyCodeObject). But after beta1, the API should be stable.